Electric furnace.



BESTAVAILABLE CGP,

2. nu mm 9. 0 8 nU .U nv t n e .1 a DI Dn. E T T DI N. H 5. o 5, 7 0. N

ELECTRIC FURNACE.

,Applclton led Nov. 21, 1901.)

(No Model.)

jizz/@Idar Aff@ BEST AVAlLABLE CGW UIT-ED Srrrfrns' PATENT Ormes.

HENRYNOEL POTTER, OF NEW ROCHELLE, NEW'YORK, AssIGNOR To' f GEO.' Wns'rxNGuousE, or rIrTsBURG, PENNsYLvAmA.

Er-Ecrans FUR-NAC E.

I SPEGIIGLI forming part o( Lettdrs Patent No. 715,505, dated. Decemberg, 1902 lApplication lodlovelblr 21.1901. Serial Ha.83.075. (Io model.)

Taa 'wltom/ it'may concern'.-

Be it known that 1, HENRY N OEL Porras,

' acitizen of the United States,-and a resident of New Rochelle, in the county of 'Westches-A ter and-Stateof New York, have invented certain new and useful Im provements in Electric Furnaces, "cstion.

\ lIn my PatentrNo. 652,640, issued' to me on .Tune 26, 1900, Ishow andfdescribe an.' electric furnaee'inwhch the main source of heat is an electrolytic tubecom posed eta mixture of dryelectrolytes and supplied with terminals lfor conveying electric current to the tube, which is Ikept in a state of incandescence by of which the followiugis a specili- .the curreutafter a preliminary heating by external means. I also show and describe in the said patent ajjacket of so me relatively poor -eouductinginaterial which may be a single one-'ofthefoomponents of the tube.

The present inventiourelates to-providing means for-preventing the current in such at "tube from ilowinz -unevenlyaby reason. of al-A most unavoidable slight differences in-specic resistance of the tube due to structural and perhaps ychemical irregularities in the tube In-eertau-embodi'mentsof my invention I provides plurality of 'terminals at each end of the conducting tube, the 'terminals be:

-ing arranged in confronting -pairs and each as stated-above.

-desredj-result -by notching the tube or by -pairconnected Y ondary or ballast resistance. The object of to a-separate converter secsuch-arrangements isto prevent the uneven -'di'strhution.of current traversing the tube,

I'lcan also accomplish the building up -a tube of alternate sections of 'relatively good andrelatively .poor conductors, or I may. make the main-heating portion in the form of rods composed of mixed dry-electrolytes embedded in the -jacket offpoorer conducting:` material, either -solid oupowdered, th rodsbeing provided vat theiropposite'ends with suitable terminals for makingconnection with an electric circuit. In the last descrbed'torm the rods are wholerth'us constituting a notched or an' interrnpted tube; but the rods may be arranged on the lines of a rectangle Or .other shape, if

preferred. The devices by means 'Oftwhich'i accomplish the described result are clearly shown in the accompanying drawings, in which- Fiure Lshows a tube having terminal connections at its opposite ends. Fig. 2 shows the tube developed into a plane, each confronting pair of' terminals being connected to a separate convertersecondary. Fig. 3 is a similar view showing each confronting pair of terminals connected with a separatehallast. Fig. 4 is a perspective of an clectrolytic tubehaving longitudinal notches.. Fig. 5 is a similar view of a tube made ofsegments composed of mixtures of dry electrolytes separated by segments of Apoorer conducting material. Fig. 6 isya perspective of an electrolytic tube made up of rods composed of mixtures of dry electrolytes embedded in a jacket Of apoorer 'conducting material, and Fig. 7 is a similar view of a tube in which the conducting-rods are embedded in a jacketing material in the form of a. powder held in place by an innerand vintenter ring.

Referring to Fig 1, ;t`necharacter 1 indicates atube'composed of a mixture of dry electrolytes, such as magnesia and alumina, the samebeing supplied with' terminals 2, 3, 4, 5, 6, 7, and 8 at one end and with correspending terminals 9, 10, 11, 12, 13, 14, and 15 at the opposite end. vThe'terminals at the opposite ends of the tube are arranged in confronting pairs. The resistance, and consequently the voltagedrop, will, therefore,with a given current'be less from any given teurminal to its direct Oppositethan to any other terminal. IE now each confronting pair of terminals be connected to a 'separate couverter-secondary or to a separate ballast re-V plane by rolling. In the arrangement illus trated in these gures the currentof anyscondary or through any ballast, should it tend to stray from 'the straight line acrossto the opposite terminalfmust traverse a' longer path,snd thus, geometrically Sp'ealiIing-path of greater resistance. In Figs and-3,should the current from the terminal 2 tend to enter terminal 10 instead of terminal 9, where it l'o pooro'onductinzmaterial.

35 stitutes for the electrolytic rods 2O 20.

BEST AVAILABLE COPS belongs, the voltage at 9 -risesand that at 10 falls in proportion to the stray current,there by tending to maintain 'even distribution from all the terminals. To accomplish the 5' same result, I may construct the electro'ly'tic tube as illustrated in Fig. 4, in which longi tndinal notches 416 16 separate or Vartllly separate vthe adjacent current-pat s. Still another means for accomplishing the same to endcousists in making the tube of segments 17 17, composed of a mixture, say, of magnesia and alumina separated by segments 18 18 of pure. magnesia or pure alumina alone. The unmixed electrolytes being poorer ccn- 15 ductors than the'mixtnres, the currents will .pass-along the better conducting segments,

as will be readily understood.

In Flig. 8 ahcxv rods 20 20, of `mixed electrolytecm ded in a jacket 19,0frelstive1y In Fig. 7 this idea lscar'ried forward a stepby showing the jacket 19 al a powder of poorly conducting material held in place by tubes 21 and 22. In

this figure the rods maybe composeebf the l5 above-described miitnm of dry electrolytes surrbunded by maguesia-powder, and ,the

v tubes may' be totA ure magnesi'a. Outside the -tube 22 I'msy p ace a block or jacket 23, of calcium oxid, as being one of the best hest 3e insulators known, or I may usesome other 4o those of the furnace described above; but the carbon rod would beadapted to take current without preliminary heating. I t will be understood that in every case a jacket is necessary, as was fully set forth in my patent al- 45 ready referred to.

' I claim as my iuvention- 1. An electric furnace, consisting of a tube composed of a mixture of dry electrolytes constituting the conducting 'portion of the fur- 5o nace, the said tube being provided with confronting electric-circuit terminals arranged in pairs at opposite ends of the tube, and the Said pairs of terminals being symmetrically spaced.

2. An electric furnace consisting of a tube composed of a mixture of dry electrolytes constituting theconducting portion of the furnace, and provided with menus for preventing the uneven distribution of current traversing 6o the tube when in use.

3. An electric furnace consisting of a tube vimos composed of 'a mixture of dry electrolytes constituting the conducting portion ci' the furnace, the said tube being 'provided with separated orpartially-sepsraied strncturali'elements-forming paths for the electric current.

terrupted tube composed of a mixture or' dry electrolytes, the tube elements constituting the conducting portion of the furnace and belngsurronnded wholly or in part by poorer conducting material. "iiie An electric furnace, consisting of an in terrnpted tube composedcf a mixture of dry electrolytes, the tube. elements constituting the conducting portion of the furnace r ud being surrounded wholly or in part by poorer conductingmaterial in powdered form.

6. An electric furnace, consisting o1' an interrupted tube of material which is conducting at theA temperature at which the furnace vis to be used,'the elements of the' tube being wholly or partially surrounded by material of lower conductivity.

7. An electric france, consisting of an iiiterrupted tube ot material which is conducting atthe temperature at which the furnace isto bensed, the elements o! the tube being 'wholly or partially surrounded by' material of lower conductivity in powdered-form. l

8. An electric furnace, consisting of a tube com posed ofa mixture of dry electrolytes and providedwith means for preventing the uneven distribution ofjcurrent in the body of the'furnace when in nseyin combination with 95 a jacket of poorer, conducting material.

9. An electric furnace, consisting of sninterrupted tube composed of material which is conducting at the temperature at which the furnace is to be used, the elements of thetube we being surrounded by powdered material cf lower conductivity, the powdered material being heldin place by tubes of poorly-com ductingl material. 4

10. Anelectricfurnace,consistingof aninfc5 terrupted tube com posed of material which is conducting at the temperature at which the furnace is to be used., the 'elements uf'thetube being surrounded by powdered material of lower conductivity, the powdered material, I'XO being held in place by tubes of poorly-con ducting material, and the outer'u'ing being surrounded by a jacket oi inert heat-resisting material.

Signed at New York, in the county of New' x15 York and State of New York, this 19th day of November, A. D. 190i.

HENRY NOEL POTTER.

Witnesses: GEORGE 1I. Srooxnnlncn, WiL H. CAPEL.

4. An electric furnace, consisting of nu in- 

